Purple martin birdhouse

ABSTRACT

A purple martin birdhouse having opaque roof structure and exterior walls of a transparent composition through which light may pass providing for a lighted interior of the birdhouse whereby starlings make no attempt to nest within the birdhouse. Preferably the exterior walls in their entirety are easily removable to expose and gain access to one or more interior compartments for cleaning between seasons, the exterior wall(s) having a separate opening for each separate compartment of the birdhouse. The birdhouse has a plurality of separate interconnected compartments with a separate entrance for each compartment defined in the respective exterior walls for that particular compartment. Preferably the entire birdhouse has tubular structure extending between the upper roof and the lower floor through which a pole is insertable and over which the birdhouse is slidable downwardly to a lower level by a line attached to the birdhouse extending upwardly to a pulley at an upper end of the pole, downwardly through the pole and around a pulley in an opening at the lower end of the pole and upwardly to an attaching point at the base of the lower floor of the birdhouse.

United States Patent [1 1 Wiener [4 1 Feb. t9, r974 [73] Assignee: Armond Industries, Inc., New York,

22 Filed: Dec. 3, 1971 21 Appl. No.: 204,523

[75] Inventor:

[52] US. Cl. 119/23 [51] Int. Cl A0lk 31/00 [58] Field of Search 119/23, 26; 254/139 [5 6] References Cited UNITED STATES PATENTS 3,696,792 10/1972 Bruhrls 119/23 3,177,849 4/1965 lsenberg 119/23 3,496,913 2/1970 Vail 119/23 3,282,251 11/1966 Dahmus 119/23 3,111,934 l1/l963 Vail 119/23 3,078,826 2/1963 Bear.... 119/23 3,367,632 2/1968 Vail 119/23 X 2,915,040 12/1959 Ward 119/23 3,094,973 6/1963 Devall.... 119/23 X 3,410,248 11/1968 Vail i 119/23 3,478,722 ll/l969 Falcone et a1. 119/23 FOREIGN PATENTS OR APPLICATIONS 61,778 10/1913 Austria 119/23 OTHER PUBLICATIONS Dearborn, Bird Houses..., Farmers Bulletin 609,

1914, pp. 12 & 13. (US Dept. of Agriculture).

Primary ExaminerJames H. Czerwonky Attorney, Agent, or Firm-La Forest S. Saulsbury et a1.

[57] ABSTRACT A purple martin birdhouse having opaque roof struc' ture and exterior walls of a transparent composition through which light may pass providing for a lighted interior of the birdhouse whereby starlings make no attempt to nest within the birdhouse. Preferably the exterior walls in their entirety are easily removable to expose and gain access to one or more interior compartments for cleaning between seasons, the exterior wall(s) having a separate opening for each separate compartment of the birdhouse. The birdhouse has a plurality of separate interconnected compartments with a separate entrance for each compartment defined in the respective exterior walls for that particular compartment. Preferably the entire birdhouse has tubular structure extending between the upper roof and the lower floor through which a pole is insertable and over which the birdhouse is slidable downwardly to a lower level by a line attached to the birdhouse extending upwardly to a pulley at an upper end of the pole, downwardly through the pole and around a pulley in an opening at the lower end of the pole and upwardly to an attaching point at the base of the lower floor of the birdhouse.

9 Claims, 11 Drawing Figures PAIENTEB FEB 1 '9 m4.

SHEH 1 (If 2 INVENTOR.

.W ELLlOT WIENER Fl (5 BY ATTORNEY PAIENIEQ FEB 1 91914 sum a BF FIGA ATTORNEY PURPLE MARTIN BIRDHOUSE This invention relates to a purple martin birdhouse of improved structure, design and function.

BACKGROUND OF THE DISCLOSURE Prior to this invention as a result of a combination of negative factors interfering with the balance of nature as civilization extends from the city areas outwardly over the countryside by ever increasing numbers of res identia] areas together with the elimination of natural habitats of wild life, problems of pest control particularly of the flying insect variety, such as flies, mosquitoes, and the like, have become increasingly serious and critical. The criticality of the situation has been further pushed forward as a result of increased immunities of such pests to various industrial insecticides as well as the current recognition by health officials that many of these insecticides further disturb the balance by providing permanent poisons to the soil and to human beings.

SUMMARY OF THE INVENTION An object of this invention is to help re-establish a balance of nature to overcome problems of the type discussed above.

Another object is to enhance the control of and substantially eliminate at least locally flying insects such as flies, mosquitoes, moths, and the like.

Another object is to provide a means to re-establish a balance of nature and by so doing prevent the extinction of the purple martin species of birds.

Another object is a particular birdhouse structure adapted to the habits and preferences of the purple martin together with being adapted contrary to habits and preferences of starlings and the like.

Another object is a particular purple martin birdhouse structured to provide ready access to the same between seasons.

Another object is a suitable birdhouse mounting means for making the house readily accessible for cleaning and/or observation.

Other objects become apparent from the preceding and following disclosure.

One or more of the preceding objects are obtainable by the invention as defined hereafter.

SUMMARY OF THE INVENTION As a result of the aforementioned extension of residential areas and industry into vast expanses of the countryside, the natural habitats of the purple martin have been substantially destroyed and environmentalists recognize that the species of the purple martin is in danger of extinction. To those not familiar with the benefits of the purple martin bird in maintaining a balance of nature, it is hereby stated that the purple martin lives and survives on solely flying insects, particularly of the mosquito variety for example, and that wherever there are groups or colonies of the purple martins, there is a substantial absence of flying insect problems because of their control by these birds. It has been known that the purple martins have several characterizing habits and preferences. For example, the birds live in colonies with one another, but insist upon and require a separate chamber or compartment for each pair for living and nesting. The birds also return each early spring to the exact or near-exact location of former years except for a particular percentage of the birds which on their return find other suitable nesting places to their preference. It has been found in the past also that man made birdhouses providing these separate compartments in an apartment house style of structure attract these birds provided that other birds are successfully excluded therefrom until these birds take up habitat therein. Although. there thus far is no known complete deterrent to the sparrow except a diligent eye of the birdhouse keeper and a cleaning out of sparrows that may attempt to invade the birdhouse prior to the arrival of the purple martin, it has been found that another primary nuisance bird insofar as occupying the purple martin birdhouse against the desires of the birdhouse keeper is the starling and that entry of the starling can be substantially prevented by the inclusion within the various compartments of material such as tinsel because the starlings do not habitate where there is shiny material such as tinsel. When a purple birdhouse is erected if it is within the design features accepted by the purple martin bird, usually during a first or second year of its erection there will come to the birdhouse possibly one or two or more pairs of the purple martins, normally at least two pairs. Thereafter it is primarily by virtue of the ever growing and enlarging family of the purple martin which from year to year increases in number to habitate in and fill up additional compartments of the purple martin apartment house. It is important however to keep excluded from the vacant compartments birds other than the purple martin or otherwise the purple martin birds will not normally remain.

Accordingly, the birdhouse structure of this invention includes a roof and floor connected by interior walls dividing the space therebetween into at least two or more compartments all exposed to an exterior wall through which light may pass such as either a translucent wall or a transparent wall. By virtue of the transparency or translucency of the exterior wall to each compartment, light entering into and lighting up the respective compartments prevents the entry of the star lings.

Each exterior wall to each compartment has its own private entrance as is a requisite for habitation of purple martins.

Each exterior wall preferably is totally removable to expose the interior compartment for the cleaning thereof.

Another primary advantage of the wall being of a translucent or transparent nature, preferably transparent, is that bird watchers may observe the actual habits and daily routines of the bird within its compartment throughout its nesting cycle. Unlike the starlings, the purple martins will and do nest in lighted areas.

By virtue of the entire outer wall being easily removable, access to clean out either between seasons or unwanted birds is readily possible.

Preferably the walls are slidably removable panels either laterally removable from in front of one or more compartments simultaneously or uprightly removable such as vertically and preferably with the vertically removable exterior wall being attached to or slidable past a roof whereby the slidable exterior wall may be raised thereby exposing all of one or more compartments.

The birdhouse may be square, triangular round, or any other desired shape consistent with the above description. In one preferred embodiment, the back and front compartments have a common side removable panel on each side of the house. In another preferred embodiment, the bird house is round and the exterior wall is a hollow cylinder slidably removable upwardly or downwardly, as might be desired and structured therefor, to thereby expose all compartments simultaneously for rapid and easy cleaning thereof. However each compartment may have a separate removable panel whereby one compartment may be opened without disturbing a nest in another compartment.

In a preferred embodiment, in order to further facilitate both observation and particularly the cleaning of the birdhouse for whatever purpose, the birdhouse is slidably mounted around a pole extending centrally through a tube connecting the roof to the bottom floor whereby the entire birdhouse may be raised or lowered on the pole, preferably by way of a hollow pole having an opening therein at each of the top and the bottom with pulleys at each location and a line attached to the birdhouse to lower the birdhouse to a desired height accessible for cleaning and thereafter to raise the birdhouse to its normal position, securing the line extending through the pole around the bottom pulley around a tree, the line also preferably being attached from the lower direction to the birdhouse whereby the birdhouse is tightly held between the opposite ends of the line to prevent the vibration or shaking of the birdhouse in the wind or the like. There of course may be more than one hole or tube extending through the birdhouse whereby the birdhouse is slidable upwardly and downwardly on a plurality of poles. Correspondingly, the pole does not necessarily have to be through the center of the birdhouse although this is a preferred design.

The birdhouse may have a plurality of intermediate floors or may be a single floor and also may be a plurality of sections of one or more floors each mountable one on top of the other between the lower floor and the upper roof in the nature of a beehive type of arrangement.

By virtue of this invention, a simple and inexpensive purple martin birdhouse may be mass produced for use in residential areas whereby people may now enjoy their mornings, afternoons, and evenings out of of doors without the problem of infestation of mosquitoes and the like. I

THE FIGURES FIG. 1 illustrates a perspective view of a typical purple martin birdhouse of this invention, illustrating in phantom the position of two opposite sides of the birdhouse when slid into an open position exposing the compartments thereof. each of the sliding portions being transparent.

FIG. 1A is a cross section along lines lA-lA.

FIG. 2 illustrates an alternative embodiment shown in cross-section to better illustrate the sliding relationship of the slidable panels as well as to illustrate the sliding mount characteristics of the birdhouse mounted on a tube slidably mounted around a pole for raising and lowering the birdhouse with with the line for raising and lowering the house extending around upper and lower pulleys and through the center of the pole.

FIG. 3 illustrates a particular corss-section of the pole and of the tube on which the birdhouse is mounted illustrating how the mounted tube can be prevented from rotating as a result of wind or the like.

FIG. 3A illustrates an alternative embodiment in cross-section showing how rotation of the tube around the pole can be prevented.

FIG. 38 illustrates a still additional mechanism, a ragged edged piece of metal being securable whereby when the upper end of the tube on which the birdhouse is mounted is pressed upwardly against the teeth, rotation of the birdhouse tube is prevented.

FIG. 3C illustrates another variation in which each tube on which the birdhouse is mounted and the pole are both completely rounded and cylindrical, but with a separate cap being mountable on the lower or upper end of the birdhouse-mounting tube and with the guide strip being mounted on the pole, whereby rotation of the birdhouse is prevented.

FIG. 3D illustrates still another alternative embodiment in which the upper end of the birdhousemounting tube has one or more notches therein and in which the pole includes a perforation or hole receptive of a screw shown mounted therein against which the birdhouse may be raised with the screw sliding into the slot thereby preventing rotation of the birdhouse.

FIG. 4 illustrates an alternative embodiment of the purple martin birdhouse of this invention, in which each of the floor levels are separately mountable in bee-hive fashion whereby the apartment-house file may be assumed over a period of time as the purple martin inhabitants become more and more numerous in numbers.

FIG. 5 illustrates a side perspective view showing the mounting mechanism in part in cross-section, whereby by virtue of the transparent or translucent sides extending all the way around the birdhouse, the inner compartments are visible and in which the entire side extending all the way around the birdhouse is lowerable simultaneously all the way around and slidable downward on the pole.

FIG. 6 illustrates still another embodiment of the invention in which the purple martin birdhouse is mounted securedly from above, and sidewardly extending from a mounting pole.

DETAILED DESCRIPTION OF THE INVENTION In greater particularity with reference to FIG. 1, there is disclosed a perspective view of a typical purple martin birdhouse of this invention having opposite translucent walls, one on one side of the house and the other on the other side of the house, whereby each compartment therein has at least one fully transparent wall, the particular embodiment as shown in FIG. 1 and FIG. 1A having the transparent walls as the slidable walls, although in an alternative arrangement the opaque walls may be the slidable walls if desired. Note however that for the walls to be laterally slidable as shown in FIG. 1A, the slidable wall must have the relationship as illustrated relative to the downwardly extending eaves of the roof. The FIG. 1 birdhouse 7 includes the transparent wall 8 extending from the roof 9 to the base 10 slidable in grooves 11A and 11B respectively, the birdhouse as shown in FIGS. 1 and 1A having the interior compartment walls 12A, 12B, 12C and 12D and the opaque walls 13A and 138 which in an alternative embodiment may optionally also be transparent. Because of the transparency of the walls such as wall 8, the transparent walls for the compartments considerably below the roof 9 additionally have eaves 9A and 9B for example in order to provide some degree of shade to prevent the interior of the compartment from becoming overheated due to the effect of sunlight.

FIG. 2 illustrates in cross-section an alternative shape the advantage of this narrowing shape toward the lower portion of the birdhouse as well as the advantage of the extended eaves 9' of the birdhouse being that there is less possibility for direct sunlight to enter through the transparent walls 8A and 88, whereby the compartments are maintained at livable temperatures for the purple martin inhabitants. FIG. 2 also illustrates a preferred pole and mounting system, there being the mounting tube 14 to which the birdhouse 7 is mounted, with the tube extending centrally through the birdhouse 7', and the tube M being slidable on and around a flat pole or support pole 15 having a hollow interior with pulleys suitably mounted such as pulleys 16A and 16B adjacent holes 17A and 17B whereby a line 18 mounted at 18A to the tube 14 and mounted at 188 to the tube 14 extends through the hollow interior 15A of the pole 15 whereby the birdhouse may be raised or lowered by the pulling upwardly or permitting to slide downwardly the tube 14 on the pole l5 and the position of the slidable tube 14 being capable of being set by virtue of a cleat 19 around which the line 18 is secured or securable.

FIG. 3 illustrates a typical cross-sectional view through a birdhouse-mounting tube 14A and a mounting pole 158 over which the tube 14A is rideable slidably, illustrating in particular indentation 20 in pole 15B and inwardly extending projection 21 of tube 14A.

FIG. 3A illustrates an alternative embodiment in which strip 22 is mounted by a screw 23 onto a pole 15C with the tube 148 being not fully closed along one edge and thereby slidable upwardly and downwardly on either side of the strip 22.

FIG. 38 illustrates a jagged edged flat member of resilient bendable material bendable around a pole and securable thereto with the the jagged edge directed downwardly such that when the upper portion ofa tube such as 14 is raised upwardly against the jagged teeth 24, rotation of the tube becomes impossible.

FIG. 3C illustrates a conventional tube 14D of conventional cylindrical shape mounted around a pole 15D of conventional shape, with a strip 22A mounted on the pole 15D along the axis of the pole and with a cap 25 mounted on the tube 14D having a slot 25A rideable around the strip 22A, thereby preventing rotation of the tube 14D around the pole 15D.

FIG. 3D illustrates still another structure and mechanism for preventing the rotation of the tube 14 around the pole 15, the pole 15' having screwed thereinto a screw 26 of a size slidably fittable into a preferably V- shaped notch 27 in tube 14'. The FIG. 4 illustrates a birdhouse comparable to that of FIG. 1, except that it is composed of separately mountable and/or insertable units 7A and 7B, for example easily insertable and screwed together with appropriate bolts and washers and nuts or any other suitable snapping means.

FIG. 5 illustrates a hemispherically shaped birdhouse in which the transparent hemisphere 28 circumscribes the entire birdhouse laterally and has'a hole 29 at its base sufficiently large to slide downwardly around the mounting tube ME and pole 15E when detached at points 30A and 308.

It is within the scope of this invention to make such variations and modifications on the embodiments disclosed and described as would be apparent to those of ordinary skill in this field of mechanical endeavor. Ac cordingly, obvious substitutes or variations are within the spirit and scope of this invention.

I claim:

l. A purple martin birdhouse device comprising in combination: a birdhouse compartment structure including opaque shade-producing roof structure mounted thereon and defining at least one compartment and including at least one substantially upright compartment-enclosing exterior transparent wall as a side wall receivingly transparent to two-way lighttransmission as to be transmittable of each of inside and outside light therethrough to an extent necessary for outside visual discernment of objects within said compartment, including a plurality of said compartments interconnected, and in which said exterior wall is removably mounted, and each said compartment has a separate entrance to exterior space.

2. A purple martin birdhouse device of claim I, including mounted on said birdhouse structure a solely single cylindrical structure extending uprightly between and through said birdhouse structure, and further including an elongated hollow cylindricallyshaped pole structure having a first opening at its upper end and having a second opening at substantially its base lower end, a first pulley means mounted at the first opening and a second pulley means mounted at the second opening, a cleat means mounted on said pole structure at about said pole lower end, a mounted lineattaching means on said cylindrical structure for attaching a line threadable through said first and second pulley means for raising said cylindrical structure on said pole structure, said cylindrical structure being of sufficient cross-section to be slidable over said elongated pole structure downwardly to a lower end of the pole structure, and said cylindrical structure having an upper-end surface angularly-inclined to define a predetermined seat receivable about axially, of a stopprojection, said angularly-inclined surface engaging said stop projection whenever said cylindrical structure is raised on said cylindrical pole against said stopprojection and the seat being structured such to restrain the cylindrical structure against further axial movement upwardly and such to stabilize the cylindrical structure against revolving movement.

3. The birdhouse device of claim 1. in which said exterior wall means is translucent.

4. The birdhouse device of claim ll, including at least one intermediate floor spaced between said lower floor and said upper roof and said at least one intermediate floor being joined to said intermediate walls and extending to said exterior wall such that space defined between said lower floor and said upper roof is divided into at least a lower compartment and an upper compartment.

5. A purple martin birdhouse device of claim 1, in which said birdhouse comprises a lower floor structure; upper roof structure, interior wall structure providing inner walls connecting said lower floor structure to said upper roof structure and dividing space therebetween into separate compartments each openable solely to exterior space; said exterior wall defining for each said separate compartment a quadrangular panel having parallel upper upper and lower sides, and said upright compartment-enclosing exterior wall being of a composition permitting substantially unrestricted passage of light in both directions therethrough.

6. A purple martin birdhouse device of claim 1, in which the exterior wall includes eave shade-structure mounted on said transparent exterior wall at a position such that shade is providable against direct sunlight into said compartment.

7. A purple martin birdhouse device comprising in combination: a birdhouse compartment structure defining at least one compartment and including at least one substantially upright compartment-enclosing exterior wall receivingly transparent to two-way lighttransmission as to be transmittable of each of inside and outside light therethrough to an extent necessary for outside visual discernment of objects within said compartment, including a plurality of said compartments interconnected, in which said exterior wall is removably mounted, and each said compartment having separate entrance to exterior space, said birdhouse structure including slide structure comprising substantially-horizontal groove structure mounted thereon and having at least one open-ended groove slidably receiving said panel, at least one of said upper and lower parallel sides being mounted within said groove and slidable along the groove to alternately open and close said compartment to exterior space.

8. A purple martin birdhouse device of claim 7, in which said groove structure includes grooves both above and below the slidable panel receivable respectively of each of said upper and lower parallel sides and thereby retainable of the exterior wall means except for opening sliding movement thereof.

9. A purple martin birdhouse device comprising in combination: a birdhouse compartment structure defining at least one compartment and including at least one substantially upright compartment-enclosing exterior wall receivingly transparent to two-way lighttransmission as to be transmittable of each of inside and outside light therethrough to an extent necessary for outside visual discernment of objects within said compartment, including a plurality of said compartments interconnected, said exterior wall being removably mounted, each said compartment having a separate entrance to exterior space, said birdhouse comprising lower floor structure, upper roof structure, interior wall structure providing inner walls connecting said lower floor structure to said upper roof structure and dividing space therebetween into separate compartments each openable solely to exterior space; said exterior wall defining for each said separate compartment a quadrangular panel having parallel upper and lower sides, and said upright compartment-enclosing exterior wall being of a composition permitting substantially unrestricted passage of light in both directions therethrough, and including mounted on said birdhouse structure a solely single cylindrical structure extending uprightly between and through said upper roof structure and said lower floor structure, said cylindrical structure having an upper-end surface angularlyinclined to define a predetermined seat about axially receivable of a stop projection, said annularly inclined surface engaging said stop projection whenever said cylindrical structure is raised on a cylindrical pole against said stop-projection and the seat being structured such to restrain the cylindrical structure against further axial movement upwardly and such to stabilize the cylindrical structure against revolving movement.

=l l l l 

1. A purple martin birdhouse device comprising in combination: a birdhouse compartment structure including opaque shade-producing roof structure mounted thereon and defining at least one compartment and including at least one substantially upright compartment-enclosing exterior transparent wall as a side wall receivingly transparent to two-way light-transmission as to be transmittable of each of inside and outside light therethrough to an extent necessary for outside visual discernment of objects within said compartment, including a plurality of said compartments interconnected, and in which said exterior wall is removably mounted, and each said compartment has a separate entrance to exterior space.
 2. A purple martin birdhouse device of claim 1, including mounted on said birdhouse structure a solely single cylindrical structure extending uprightly between and through said birdhouse structure, and further including an elongated hollow cylindrically-shaped pole structure having a first opening at its upper end and having a second opening at substantially its base lower end, a fiRst pulley means mounted at the first opening and a second pulley means mounted at the second opening, a cleat means mounted on said pole structure at about said pole lower end, a mounted line-attaching means on said cylindrical structure for attaching a line threadable through said first and second pulley means for raising said cylindrical structure on said pole structure, said cylindrical structure being of sufficient cross-section to be slidable over said elongated pole structure downwardly to a lower end of the pole structure, and said cylindrical structure having an upper-end surface angularly-inclined to define a predetermined seat receivable about axially, of a stop-projection, said angularly-inclined surface engaging said stop projection whenever said cylindrical structure is raised on said cylindrical pole against said stop-projection and the seat being structured such to restrain the cylindrical structure against further axial movement upwardly and such to stabilize the cylindrical structure against revolving movement.
 3. The birdhouse device of claim 1 in which said exterior wall means is translucent.
 4. The birdhouse device of claim 1, including at least one intermediate floor spaced between said lower floor and said upper roof and said at least one intermediate floor being joined to said intermediate walls and extending to said exterior wall such that space defined between said lower floor and said upper roof is divided into at least a lower compartment and an upper compartment.
 5. A purple martin birdhouse device of claim 1, in which said birdhouse comprises a lower floor structure; upper roof structure; interior wall structure providing inner walls connecting said lower floor structure to said upper roof structure and dividing space therebetween into separate compartments each openable solely to exterior space; said exterior wall defining for each said separate compartment a quadrangular panel having parallel upper and lower sides, and said upright compartment-enclosing exterior wall being of a composition permitting substantially unrestricted passage of light in both directions therethrough.
 6. A purple martin birdhouse device of claim 1, in which the exterior wall includes eave shade-structure mounted on said transparent exterior wall at a position such that shade is providable against direct sunlight into said compartment.
 7. A purple martin birdhouse device comprising in combination: a birdhouse compartment structure defining at least one compartment and including at least one substantially upright compartment-enclosing exterior wall receivingly transparent to two-way light-transmission as to be transmittable of each of inside and outside light therethrough to an extent necessary for outside visual discernment of objects within said compartment, including a plurality of said compartments interconnected, in which said exterior wall is removably mounted, and each said compartment having a separate entrance to exterior space, said birdhouse structure including slide structure comprising substantially-horizontal groove structure mounted thereon and having at least one open-ended groove slidably receiving said panel, at least one of said upper and lower parallel sides being mounted within said groove and slidable along the groove to alternately open and close said compartment to exterior space.
 8. A purple martin birdhouse device of claim 7, in which said groove structure includes grooves both above and below the slidable panel receivable respectively of each of said upper and lower parallel sides and thereby retainable of the exterior wall means except for opening sliding movement thereof.
 9. A purple martin birdhouse device comprising in combination: a birdhouse compartment structure defining at least one compartment and including at least one substantially upright compartment-enclosing exterior wall receivingly transparent to two-way light-transmission as to be transmittable of each of inside and outside light therethrough to an extent nEcessary for outside visual discernment of objects within said compartment, including a plurality of said compartments interconnected, said exterior wall being removably mounted, each said compartment having a separate entrance to exterior space, said birdhouse comprising lower floor structure, upper roof structure, interior wall structure providing inner walls connecting said lower floor structure to said upper roof structure and dividing space therebetween into separate compartments each openable solely to exterior space; said exterior wall defining for each said separate compartment a quadrangular panel having parallel upper and lower sides, and said upright compartment-enclosing exterior wall being of a composition permitting substantially unrestricted passage of light in both directions therethrough, and including mounted on said birdhouse structure a solely single cylindrical structure extending uprightly between and through said upper roof structure and said lower floor structure, said cylindrical structure having an upper-end surface angularly-inclined to define a predetermined seat about axially receivable of a stop projection, said annularly inclined surface engaging said stop projection whenever said cylindrical structure is raised on a cylindrical pole against said stop-projection and the seat being structured such to restrain the cylindrical structure against further axial movement upwardly and such to stabilize the cylindrical structure against revolving movement. 